Restriction Enzyme Can Be Used to Limit the Length of the DNA Template Available for the Transcribing Polymerase

The DNA region that is directly contacted by the transcription complex is larger than the area required for mRNA synthesis alone. How much DNA is required for transcription can be assessed by a number of methods, one of which is limiting the length of DNA by using restriction enzymes. These enzymes cleave at specific “recognition sequences” that are embedded at specific location along the DNA template. We can either use existing sequences or insert new ones at locations of our choice by means of site-directed DNA mutagenesis.